Will the World Have Enough Energy in 2040?

Earth at Night: This composite image shows a global view of Earth at night, compiled from over 400 satellite images. | NASA

By 2040, planet Earth will be home to nearly 9 billion people — up roughly 2 billion from today — all requiring access to energy supplies in order to participate in modern life. We have the natural resources to meet global projected energy demands in 2040, but how to do so equitably and without exacerbating global warming are more difficult questions, experts said at a AAAS event.

The challenges will be less acute in the developed world, where energy use is projected to stay mostly steady in the next three decades. But the next 30 years should see energy demand surge in other countries whose economies are growing rapidly, especially those in Asia, according to representatives from ExxonMobil and the Energy Information Administration (EIA), which is part of the U.S. Department of Energy.

Though they differ in their finer points, projections by both organizations show global energy use growing from roughly 400 quadrillion Btus in 2000 to over 700 quadrillion Btus by 2040 with virtually all of the increase coming from outside today's high-income countries. At that point, less than half of the world's oil resources will be consumed, according to Rob Gardner, manager of the Economics and Energy Division of ExxonMobil's Corporate Strategic Planning Department. The company also estimates that the remaining recoverable global resources of natural gas are enough to meet current demand for about 200 years.

More than 70%

The relative contribution from Asian countries, excluding Japan and South Korea, to the projected world increase in energy-related CO2 emissions between 1990 and 2040.

EIA International Energy Outlook 2013

EIA International Energy Outlook 2013 | Adapted by Janel Kiley

A concerted effort will be necessary, however, to ensure that this energy is made available to everyone who needs it, said Vivien Foster, sector manager in the Sustainable Energy Department at the World Bank.

Gardner, Foster and Howard Gruenspecht, deputy administrator of the EIA, shared their thoughts in a discussion entitled "Energy Outlook, a View to 2040," at AAAS on 21 October. The event, the first in an annual series of three Global Challenge Lectures, was moderated by National Public Radio science correspondent Richard Harris and co-sponsored by Georgetown University's Program on Science in the Public Interest, AAAS and the American Chemical Society. The full event can be viewed on C-SPAN.

The World Bank sees access to energy services as "a huge global equity issue," said Foster. Currently about 1.2 billion people live without electricity, including many in Africa, where the generation capacity available to the entire continent roughly equals that of California and Oregon, according to Foster. Globally, 2.8 billion people are still cooking on traditional stoves, with firewood, or cattle dung, or some other form of traditional biomass for fuel.

"Not only is that very inefficient and potentially very damaging to the environment, but it has huge health implications." Foster said. "About 3.5 million people are dying every year from indoor air pollution - from inhaling smoke from this kind of very primitive form of cooking."

Even when energy is available in the developing world, it is expensive and often unreliable, affecting economies. In about one-third of the World Bank's client countries, firms cite energy as the number one constraint to doing business, Foster said.

For these reasons, the World Bank Group's president, Jim Yong Kim, has joined the U.N. secretary-general Ban Ki-moon as co-chair of the Sustainable Energy for All initiative, which aims to achieve universal energy access by 2030. But, "under business as usual, there's no way we're going to meet the 2030 goal," Foster said. "We really have to start doing things very differently." Currently, for example, efforts to scale up resources for energy access are only attracting about $10 billion per year in financing, but the World Bank estimates that about $50 billion dollars per year are needed.

Vivien Foster of the World Bank, on the challenges of establishing universal energy access. | AAAS/Carla Schaffer

On the demand side, the biggest driver of energy use is change in per capita income, said Gruenspecht. "The response to growing income is not the same in the developing countries and the developing world. In fact, energy use in the developing world may be more sensitive to growth in income," he said, because consumers there will be buying cars and appliances for the first time, and requiring infrastructure that did not previously exist.

Population growth is also an important factor, which is why the EIA predicts that energy demand will increase substantially in the Middle East, and Gardner cited Africa as a region that will also be an important future energy consumer.

Will it be possible to "make energy available for all without cooking the planet?" asked Harris. He noted that the Intergovernmental Panel on Climate Change has recently estimated that in order to hold global warming at 2 degrees C above the pre-industrial level, human activities can only add about 1 trillion tons of carbon to the atmosphere, and half of that has already been added. The projections of energy use presented by Gruenspecht and Gardner, which are consistent with other forecasts, do not meet that carbon goal.

20 billion metric tons

The projected amount of the world's energy-related CO2 emissions that will come from coal in 2040. Together, coal, natural gas and liquid fuels will account for 45 billion metric tons of CO2 emissions.

EIA International Energy Outlook 2013

If the increasing demand for energy cannot be tempered, other options to reduce greenhouse gas emissions may be to increase the role of renewable energy sources or to make energy-consuming devices or processes more efficient. The U.N.'s universal energy access initiative, for example, aims to double both the contribution of renewables in the global energy mix and the rate of energy efficiency by 2030.

However, while the use of renewable energy sources is expected to increase by 2040, particularly in the developed world, wind and solar likely will account for about 10% of the global electricity supply, compared to hydropower at about 15%, according to ExxonMobil's projections. Across all demand sectors, most of the world's use of renewable energy will come from biomass, said Gardner. Likewise, the EIA estimates that without major changes in policy, the portion of the global energy mix coming from fossil fuels will decrease only modestly, from about 85% today to about 75% in 2040.

"It's still pretty much a fossil fuel world unless the world makes [very different] policy decisions," said Gruenspecht.

The fact that energy use is expected to stay relatively flat in high-income countries is largely due to increases in energy efficiency. China has also made significant improvements in energy efficiency, according to Gruenspecht. Globally, increased efficiency in transportation fuels will make a significant impact on energy consumption, predicted Gardner.

Because technological advances are critical to the evolution of the energy industry, some may wonder whether a major technology breakthrough could transform global energy use the way mobile phones and cellular networks have transformed communications.

This scenario is unlikely, the panelists agreed. While technology will bring costs down, today's energy infrastructure is so massive and well-established that radical changes would be difficult, said Gardner.

Continue to more AAAS news coverage of the 2013 "Science and Society: Global Challenges" series.